Tool useful in recovering well tubing, well casing, etc.



May 27, 1941. G. D. JOHNSON TOOL USEFUL IN RECOVERING WELL TUBING, WELL CASINGS, ETC.

Filed Aug. 16, 1938 3 Sheets-Sheet 1 May 27, 1941. G. D. JOHNSON TOOL USEFUL IN RECOVERING WELL TUBING, WELL CASINGS, ETC

Filed Aug. 16, 1938 5 Sheets-Sheet 2 May 27, 1941. G, D, JQHNSON 2,243,099

TOOL USEFUL IN RECOVERING WELL TUBING, WELL CASINGS, ETC.

Filed Aug;` 16,v 1938 5 Sheets-Sheet 5 Patented May 27, 1941 UNtrE STATES TOOL USEFUL IN RECOVERING WELL TUBDN G, WELL CASING, ETC.

Application August 16, 1938, Serial No. 225,105

18 Claims.

This invention relates to a well tool and relates more particularly to a tool for parting or facilitating the parting of casing, tubing and the like in wells. A general object of this invention is to provide a practical, effective and dependable tool of the character just mentioned.

Another object of this invention is to provide a tool that is operable to split, fracture or burst a coupling of a string of pipe, tubing or casing in a well to weaken or break said coupling so that the portion of the string above the same is free for removal from the well.

Another object of this invention is to provide a tool of the character mentioned in which the knives or parts for splitting, bursting or fracturing the tubular object in the well are actuated by the discharge of an explosive, by pres' sure generated by a chemical reaction, or by the discharge and resultant expansion of a uid under pressure. It is a feature of the present invention that the cutters or knives are actuated by a pressure generating means contained in the tool making it unnecessary to apply heavy forces to the string or line handling the tool. The tool of the present invention may be fully operated to burst, split or fracture a collar, or the like, of a tubular string in a well Without applying heavy strains to the tool and, therefore, without endangering the tool, the operating string, or the other equipment. This feature of the invention allows the tool to be operated in tubing of small diameter where it would be impractical to apply heavy operating forces to the tool from the ground surface.

Another object of this invention is to provide a tool of the character mentioned that embodies novel controls for preventing premature actuation of the pressure generating means.

Another object-of this invention is to provide a practical, dependable means for securing the body or charge carrying member of the tool to the casing or tubing to prevent it from moving under the reaction of the explosion or pressure, which means is readily releasable to provide for the withdrawal of the tool from the well at the completion of its operation.

A further object of this invention is to provide a tool of the character mentioned that may be successfully and fully controlled and operated by a wire line or cable.

A further object of this invention is to provide a tool of the character mentioned that may be designed to burst, cut or otherwise weaken a coupling or other part of a string of well casing or well tubing, or that may be designed to weaken or separate a threaded joint of the string of casing or tubing.

The various objects and features of my invention will be fully understood from 'the following detailed description of a typical preferred form and application of the invention, throughout which description reference is made to the accompanying drawings, in which:

Fig. 1 is a side elevation of the tool provided by this invention in position in a portion of a Well tubing prior to its operation, showing the tubing in vertical cross section. Fig. 2 is an enlarged side elevation of the lower portion of the tool with certain portions broken away to appear in vertical cross section. Fig. 3 is an enlarged longitudinal detailed sectional view of the intermediate portion of the tool showing the mandrels in elevation. Fig. 4 is an enlarged longitudinal detailed sectional view of the upper portion of the tool with the mandrel in elevation. Fig. 5 is a View similar to Fig. 2 showing the friction means or tail-piece released and illustrating the knives in elevation. Fig. 6 is an enlarged side elevation of the intermediate portion of the tool withl certain parts broken away to appear in vertical Y cross section and illustrating the knives partially expanded. Fig. "I is a View similar to Fig. 6 illustrating the principal parts in longitudinal cross section and showing the knives engaged in the recess of a coupling. Fig. 8 is an enlarged longitudinal detailed sectional view of the upper portion of the tool showing the mandrel in elevation and illustrating the gripping means in engagement with the tubing. Fig. 9 is a fragmentary longitudinal sectional viewof a portion of the tool with certain parts in elevation and illustrating the knives in their fully actuated positions. Figs. 10 and 11 are enlarged transverse detailed sectional views taken as indicated by lines Ill-I0 and I I-I I, respectively, on Fig. 2. Fig. 12 is an enlarged transverse detailed sectional View taken as indicated by line I 2-I2 on Fig. 3 and Figs. 13 and 14 are enlarged transverse detailed sectional views taken as indicated by lines l3-I3 and Ill- I4 on Fig. 4.

'Ihe tool of the present invention may be said to comprise, generally, an upper mandrel I0, a lower mandrel Il, a body l2 interposed between the mandrels I0 and II and related to the mandrels for relative Vertical movement, cutters or knives I3 carried by the lower mandrel Il, controlled abutment means I4 on the lower mandrel II engageable by the knives I3to eiect their expansion upon downward movement of the body I2 and the mandrel ll, means l5 asso- 1 cable.

ciated with the upper mandrel I and the body I2 for engaging a tubular object 0 in a well to hold the body I2 against upward movement, pressure generating means I6 contained in the body I2 operable to move the lower mandrel II downwardly to effect the sudden expansion of the knives I3, and other parts, the functions and details of which will be hereinafter described.

The upper mandrel I0 is adapted to be connected with an operating string or line. Where the tool of the invention is employed in the recovery of well tubing or the like it is preferred to operate it on the lower end of a wire line or In the present disclosure it will be assumed that a wire line (not shown) is connected with the upper mandrel I0 to manipulate and control the tool. The upper mandrel I0 is an elongate member considerably smaller in diameter than the tubing or object 0. A sub or coupling member I1 of increased diameter is threaded on the upper end of the mandrel I0.

It is preferred to associate a weight element withI the mandrel I0 to assure the control or actuation of certain parts by gravity. This weight element may take the form of a stem I8. Jars I9 may be connected between the stem I8 and the upper end of the member I1 and a rope socket 20 may be provided on the upper end of the stem I8 to connect the tool with the operating line or cable (not shown). As best illustrated in Fig. 14 of the drawings the upper mandrel I0 has a flat sided enlargement 2I projecting laterally from its opposite sides at a point between its ends. The lower portion of the upper mandrel I0 is reduced in diameter to constitute a stem 22. A collar 23 is secured to the upper end of the stem 22 and forms an abutment on the mandrel I0 spaced below the above described enlargement 2 I The collar 23 may be threaded on the stem 22 and may be locked in place by a set screw 24.

'Ihe lower mandrel II is an elongate part that carries the knives I 3 and the controlled abutment means I4. 'I'he lower end of the mandrel II is preferably provided with a guide or bull nose 25 to assist in guiding the tool through the tubing or object U. The lower mandrel II has an enlargement 26 spaced below its upper end. This enlargement 26 may be substantially cross-shaped in transverse cross section having a plurality of circumferentially spaced lugs 21, as best shown in Fig. 10. 'I'he portion of the lower mandrel I I above the enlargement 26 constitutes a plunger 28 for the purpose to -be hereinafter described. The plunger 28 is provided with two diametrically opposite projections 29. In the preferred construction the projections 23 are the end portions of a block xed in a horizontal slot 30 in the plunger 28.

The body- I2 is an elongate member or assembly interposed between the mandrels I0 and II and shiftably connected with the mandrels. In the construction illustrated the body I2 includes two sections, namely, an upper section 3| and a lower section 32. The sections 3| and 32 may be threaded together. In the particular construction illustrated the lower section 32 has a pin 33 on its upper end threaded into the lower end of the section 3I. The section 3I is tubular having a central longitudinal opening 34 receiving the lower portions of the upper mandrel III. The lower major portion of the opening 34 is enlarged in diameter to receive the collar 23 with suitable clearance. 'Ihe stem 22 extends longitudinally through the enlarged lower portion of the opening 34 with substantial clearance. The invention includes means for initially releasably connecting the upper mandrel I0 and the body I2 against relative vertical movement. This means may comprise a shear pin 35 arranged through transverse openings in the mandrel I0 and the upper portion of the body section 3|. vided to yieldingly resist relative longitudinal movement between the upper mandrel I0 and the body I2 following the fracturing of the shear pin 35. This yielding means preferably comprises a helical spring 36 in the enlarged lower portion of the opening 34. The spring 36 is shown arranged under compression between the collar 23 and the upper end of the pin 33 in surrounding relation to the stem 22.

T'he lower lbody section 32 is preferably of the same external diameter as the upper section 3l, the two sections being proportioned to move through the tubing or object 0 with suitable clearance. An opening 31 is provided in the upper part of the body section 32 to receive the lower portion of the stem 22 with clearance. A vertical opening 38 enters the body section 32 from its lower end and receives the upper portion or plunger 28 of the lower mandrel I I. The upper part of the opening 38 forms the cylinder or chamber of the means I6, as will be hereinafter described. Vertical slots 40 are provided in the lower portion of the body section 32 to slidably or shiftably receive the projections 29. 'Ihe slots 4I) are of sufficient length to provide for vlimited vertical movement of the lower mandrel II with respect to the body I2. Means is provided to releasably connect the body I2 and the lower mandrel II against relative vertical movement. This means may take the form of a shear pin 39 arranged through transverse openings in the lower portion of the section 32 and the plunger 28. The shear pin 39 serves to initially hold the parts in the positions where the projections 29 are in the upper ends of the slots 40.

The cutters or knives I3 are provided to cut through, slit or burst the tubular object Il. 'I'he knives I3 are preferably such that they operate to either separate or peel apart two threaded together portions of the object Il or burst, slit or weaken a threaded coupling of the object Il so that the object is parted or weakened to :be readily parted. In the typical construction illustrated in the drawings the object 0 comprises a plurality of lengths or'sections 4| connected by threaded collars 42.. 'I'he particular knives I3 illustrated in the drawings are designed to cut out through or burst a collar 42 of the object 0 to part the collar or to weaken the same. The invention contemplates that the knives I3 be formed or shaped to enter between a collar 42 and the upper portion of a section 4I threaded therein to weaken or break the threaded connection.

'I'he knives I3 are provided on the upper portion of the lower mandrel II being supported by the above described lugs 21. In practice there may be any suitable number of knives I3. In the construction illustrated there are four equally spaced lugs 21 and each lug supports a knife I3. The lugs 21 are bifurcated, having vertical slots 43. and the upper portions of the knives I3 are received in the slots. Pins 44 pass through transverse openings in the knives I3 and have their end portions carried in openings 45 in the lugs. The pins 44 serve to support. the knives I3 for pivotal movement about horizontal axes.' The lower ends of the knives I3 are bevelled down- Means is pro- 0 when they hang 1 the lower mandrel i t;

pi'ece or` spring assembly. In `the form of the invention 'illustrated the means i6 includes two vertically spaced sleeves ll and 68 shiftable on The sleeves dl and 68 are preferably of substantial length' and .have oppositely, facing or opposing shouldersk provided with annular grooves 69.1 spaced outwardly bowed leaf springs 66 extend between the sleeves Aexpansion or projection of the knives. The means I6 is in the nature of a tail on the ways 64 movable in ltl'ie 20.

41 and 48. The end parts of the leaf springs 50 may be secured to the sleeves li'landV 68-by rivets 52 or the like. The end portions lof the leaf springs 5I) are received in thegrooves 69. The springs 50 are bowed outwardly to friction,-

ally engage the interiorof the tubular object 0.

This engagement of the springs 56 with the interior of the object il resists movement of the abutment means M through the object.

The upper end portion of the sleeve 6l is preferably enlarged in diameter.l Notches 53 are provided in the upper end of ing of the knives. Means is turning of the abutment'means id with respect to the mandrel il. A longitudinal groovevl is formed in the mandrel il and the sleeve il carmeans I li on the man- The pin 55 is freely shiftable vertically 1n the groove 56.

Releasable means is vent downward movement of the mandrel il provided to prevent 'lli is arranged in the `Il for more extensive vertical movement with respect to the means i6.

The means l5 is in the nature o a slip means for gripping the interior of the tubing or object The slip means i6 includes a member 66 arranged on the 'upper mandrel i6 between the connecting member Il and the enlargement v2|.

In the preferred construction the member 63 is slidable` orshiftable on the mandrel I6. lower end of the member 66 normally rests on the enlargement ZI and the upper end of the member'63'is vnormally spaced below the lower end of the connecting member il. The .member 63' is provided with lcircuxn ferentlally spaced Vdownwardly and inwardly inclined ways 6ft.

Each oi the `ways i643 has a dove-tailed longltudinally extending groove 65. Slips are slldable and have dove-tailed tongues 6l grooves 65. the slips 66 are 'toothed to grip ftheobject Il. topreventyupward movement of the slips 'and the p a'rts connected therewith,

Connections are provided between the slips 66 and the body I2whereby the cooperation of the slips with the object 0 may prevent upward movement of the body i2. slots te are provided m the lower I-portions 4of the slips 66 and similar slots 69 are provided in the upper portion of the body section 3l. v'Links 'Ill are received in the slots 68 and 69 and are pivotally connected with the slips 66 and the body section 3l by pivot pins j.

1I. The links 'I6 are substantially vertical.

The invention froml the member I1 tothemember 63 to cause the mem# ber 63 to movedownwardly with the mandrel Ill.v This means includes aligned longitudinal sockets 'I2 and I3 in the opposing ends of the members Il and'63. 'A helical compression spring opposing registering sockets 'F2 and 13. The spring M surrounds the mandrel i6 and is arranged under compression between the end Walls of the sockets, The spring ldis operable to cause the member 63 to move downwardly with `lthe'l mandrel l@ during downately preceding generating means described.

i6, asv will be hereinafter 'I he pressure generating means i6 is operable pointed out, the presf Yl'nfll/ benny suitable y Y. fimeans operable to genera within the tool.

In the form of the invention herein described the means I6 includes a charge 16 ofexplosive.

in. the upperl The explosive charge 16 is contained The The outer sides of the interior of .includes yieldable means for J 'transmitting downward movement 'lowered until the knives I3 enter the space or opening 71 extends downwardlyin-thebody sec.- tion 32 from the opening 31 to theupper end i of the opening 38. The opening 11'has a reduced lower end portion and a percussion cap- 18 is set in this reduced' part of the opening 11. The cap 184 is located at the upper endof the charge 16. The means I6 further includes a ring pin |9. The pin I9 extends from the lower end of the stem 22 and projects down inthe opening 'l|.4 In practice the pin 'I9 may be a reduced extension of the stem 22. rlhe lower end oi the pinv19 is preferably pointed to :I'lre the percussion cap 18. With the parts in the normal or initial positions the lower end ofthe firing pin 19 is spaced a considerable distance above the cap 18.

In operation the tool is" assembled with the. parts in the positions illustrated* in Figs. 1 to f1', inclusive, and Figs; 10 to 14, inclusive, of the drawings. When the tool is in this .condition the shear pin 35 holds the upper mandrel I0 andl the body I 2 against relative movement ahdfthe shearI pin 39 holds the body I2 and the lower mandrel The spring 14 operates to'cause the member 63 to i move vdown with the downwardlyt'raveling ma drel II)v andthe downwardly moving member 33 aetuates the slips the interior oi the object The spring 14, maintains` thecleara'nce between'the. upperv end oi 1'5v the member- 63 and the lower end of theI member I1 until the slips 66 have been set or actuated. The downward movement of the mandrel I0 is continued subsequent to the settingof the slips ss. The above described downward movement of the mandrel I0 during the setting oi' the slips 33 brings the ming pm is to a. position where its v .pointed end is adjacent the cap 18. as shown in endofthe pin 1 Fig. l7. The continued downward movement/of the' mandrel I0 takes up the v'clearance between the members 63 and I1 andbrings the pointed 9 into engagement with the percussion cap 18. Thus the explosive charge 16 'Y isilredsubsequent to the setting of. the slips 3.8.

II against relative movement. The' latch pin 60 l is in the lower portion of the slot 56. The tool is run down through the tubing or object Il 'on the lower end of an operating string or cable in as# sociation with the stem I8 and the jars I9. The tool is lowered to a position. adjacent the, point l where it is desired -to part the tubing or object. 4 The tool is then raised to release the' means I4 from the mandrel I I. During upward* movement of the tool the springs 5o oooperete with the mterior oi the object 0 to resist upward movement y ofthe means I4 and the pin p6!)v moves up in the slot 5d until its head reaches the enlarged part 51 of the slot, wherepor'iA the spring 62 withdraws the pin from the slot. This frees or releases the lower mandrel II from the abutment means Ill. The tool is then lowered. Duringthis initial downward movementv of. the tool the springs 50 resist movement of the means I4 andthe mandrel II moves down with respect Vto theA means I4. During this relative movement-the lower ends of the knives I3 engage the inclined walls of the notches 53 and this engagement causes outward pivoting of the' knives I3. The. knives I 3 move into sliding or dragging coopera.: tion with the interior of the object 0. The tool is groove in a collar 42. When the knives I3 enter the collar i2 their lower ends engage the upper l When the charge 'I6 is ignited the pressure generated above the plunger 2i!v moves the vplunger and the mandrel II down with respect to the ends or corners resting on body I2. It is to be observed l thatl the slips. gripping the interior of the object Il' positively vhold the vbody I2 against upward movement. The downward movement l with respect to the body I2 of the mandrel' II v results in breaking of the shear pin 39 and results in furtherprojection of the knives the charge 'I6 the knives I3 have their low'er the upper end ora tubing section 4I and when the l,charge forcibly moves the mandrel II downwardly 'the vend 'of the tubing section forms .an abutmentifor vthe end of a tubing 'section 4I andthe engagement of the knives with the end of the tubing sectionf.

resists or prevents further downward movement 60 movement of the tool results inbreakin'g ofthew he shear pm 35. 'I'he knives I3 engaging V.in t l coller 42 'noidjthe lower mandrel l I and the body I2 against downward movement andthe weight ted with the .upper 4mandrel vLII) moves the rrheazndrel I0 downwardly with suiilcient lforce to A element I 8 together with the other partsiconbreak the shear pin 35. The shearing or breaking. v

ofthe pin 35 releases the mandrel I0 fromthe body l2 so there may. move dove wlth respect to the bodylknives and causes the knives to be plvoted outwardly as they4 bodily move downwardly with the mandrel I I., Thus the knives I3 are projected to cut through the collar 42 somewhat in 4the manner shown in Fig. 9. As. previously described, therknives I3 may be designed to wedge down' between the collar 42 vand the lower tubing section'4I connected therewith to release on weaken the threaded. section. Where the knives I3 are projected out .to out through the collar 42 .as shown in Fig. 9, they break or greatly 5by weaken the collar 42.

Following the actuation of the tool as above described the tool is withdrawn from the object 0 by pulling it upwardly. Upon upward movevment of the tool the mandrel I0 moves up and its enlargement 2I engages the bottom ofthe member B3-to move thel member up with respect to the' slips- 66. This releases or retracts the slips 86 so 4that the tool: is free for upward re- I 'moval' from the object 0. Following the removal of the tool from the well the' portion of the object 0 above the collar 42 cut or parted by the knives I3 may be readily pulled from the well.

It is to be observed that the tool of the present invention may be operated while in the well without the `in iposition oi heavy forces from the ground surface. The tool is fully actuated 4by merelyraising and then lowering the. operating string or line connected with it.- The pressure generating means I6 is contained within the tooland is operable to supply sumcient force 66 out into engagement with I I3. Prior to the ming of for the actuation of the knives I3 without endangering'any of the equipment.

Having described only a typical preferred form and application of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or modiiications that may appear .to those skilled in the art or fall within the when ignited to further actuate the knives to penetrate or spread the coupling, and means for fixing the charge.

2. A tool useful in parting the couplings of a tubular object in a well comprising an assembly to be lowered into the object and including relatively movable members, a knife associated with the assembly and operable outwardly Vto part or weaken the objectupon relative movement between said members, abutment means lengaging the interior of the object and engaged by the knife to project the knife to locate and engage in a coupling of the object upon simultaneous movement of the members, means operable to engage the interior of the object to prevent movement of one of the said members,

and means carried by the assembly operable tol generate uid pressure to move the other member following actuation of the last mentioned means to complete projection of the knife.

3. A tool useful in parting a tubular object in a well comprising a body to be entered in said' object, a section shiftable with respect to the body, a cutting element carried by said section, means operable by downward movement of both the body and section to initiate engagement of the cutting element with. the object, said element being further projectable upon relative movement between the body and section, slip means for gripping the interior of the object to positively hold the body against upward movement, and means for generating iluid pressure between opposing surfaces of the body and section to forcibly move the section downward subsequent to actuation of the slip means to further project the cutting element.

4. A tool useful in parting a tubular object in a well comprising a ,body to be entered in said object, a section shiftable with respect to the body, `a cutting element carried by the section, means shiftably carried by the section engaging the object to have its movement resisted thereby and forming an abutment engageable by the cutting element to effect initial engagement of the element with the object, the cutting element being further projectable upon downward movement of the section, and means for generating fluid pressure between opposing parts of the body and section for moving the section downward following said initial engagement of the element with the object.

5. A tool useful in parting a tubular object in a well comprising a body to be' entered` in said object, a section to be entered in said object, a. section shiftable with respect to the body, a cutting element carried by the section, meansl shiftably carried by the section engaging the object to have its movement resisted thereby and forming an abutment engageableby the cutting element to effect initial engagement ci the element ther projectable upon downward movement of y wlth the object, the cutting element being furthe section, means engageable with -the object to hold the body against upward movement, and

explosive means Kfor moving the section downward subsequent to actuation of' the last means.

6; A tool useful in parting a tubular object in a well comprising a body to beentered in said object,- a section to be entered in said object, a

section shiftable withrespect to the body, a cutting element carried by the section, means shiftably carried bythe section engaging the object to have its movement resisted thereby and forming an abutment engageable by the cutting element to velect initial engagement of the element with the object, the cutting element being further proj ectable upon downward movement of the section, means engageable with the object to hold the body against upward movement, and

explosive means for moving the section down-v ward subsequent to actuation of the last named means, the explosive means comprising a. cylinder in the body, an explosive charge inAA the cylinder and a, plunger on the section acted on by said charge.

7. A tool useful in parting the couplings of a tubular object in a well comprising, a body to be entered in the object, a section shiftably carried l a cutter pivoted on the section to be by the body, projectable therefrom into contact with the object, abutment means frictionally engaging in the object engageable by the cutter rto initiate projection thereof upon downward movement of the section vwith respect to the abutment means whereby the cutter may engage in a coupling upon movement of the tool in the object, anchor means operable to hold the body against movement, and iiuid pressure generating means in the body for moving the section. downward following actuation of the anchor means to complete projection of th'e cutter.

8. A tool for parting the couplings of a tubular object in a well comprising a body tobe entered in the object, a section shiftably carried vby the body, a projectable knife on the'section engageable with the object and projectable upon downward movement of the section, and abutment means frictionally engaging in the object and engageable by the knife to project the same upon movement of the body relative to the abutment means whereby the knife .may locate and engage in a coupling, explosive means in :the body for moving the section downward to project the knife to part or weaken the coupling,

9. A tool for use in a tubular` object in a well comprising a body to be entered in the object, an upper mandrel shiftable with respect to the body, a lower mandrel vertically shiftable with respect to the body, knives on the lower mandrel engageable with the object and projectable upon downward movement of the lower mandrel, fluid pressure generating means in the body operable 'to move the lower mandrel down, and means operable upon downward movement oi the upper mandrel for actuating the last named. means.

10. A tool for use in a tubular object in a well comprising a body to be entered in the object, an upper mandrel shiftablc with respect to the body, a lo'wer mandrel vertically shiftable with respect to the body, knives on the lower mandrel engageable with the object and projectable named upon downward movement of the lower mandrel, an explosive charge in the body for moving the lower mandrel down to project the knives, and means operable by downward movement of the upper section for firing the charge.

11. A tool for use in a tubular object in a well comprising a body to be entered in the object, an upper mandrel shiftable with respect to the body, a lower mandrel shiftable with respect to the body, knives on the lower mandrel engageable with the object and projectable upon downward movement of the lower mandrel, an explosive charge in the body for moving the lower mandrel down to project the knives,v slip means engageable with the object to hold the body against upward movement, and means operable by downward movement oi the upper section for firing the charge.

12. A tool useful in parting a tubular object in a well comprising a body to be lowered into the object, a knife part carried by the body for forcible projection therefrom, means for lowering and suspending the body, fluid pressure generating means carried by the body operable to forcibly project said part to break throughpr weaken said object, and control means operable by vertical movement of the lowering and suspending means for causing pressure generating means.

13. A tool useful in parting a tubular object in a. well comprising a body to be lowered into the object, a knife part carried by the body for forcible projection therefrom, means for lowering and suspending' the body, fluid pressure generating means carried by vthe body operable to forcibly project said part to break through operation of the lluid or weaken said object, means operable by vertical manipulation of 'the lowering and suspending means for engaging in the object to hold the body against movement when the pressure generating means is in operation, and a control operable by vertical manipulation of the lowering vand suspending means for initiating operation of the fluid pressure generating means.

14. A tool useful in parting a tubular object in a well comprising a body to be entered into the object, a carrier shiftable relative to the body, a knife part carried by the carrier for forcible projection therefrom, cylinder and piston el'ements on the body and carrier, means for generating fluid pressure in the cylinder to cause movement of the carrier relative to the body, 'means for projecting said part when the carrier is moved relative to the body, means for lowering and suspending the body, and means operable by vertical manipulation of the last named means for operating the pressure generating means.

15. A tool useful in parting a tubular object in a well comprising a body to be entered into the object, a carrier shiftable relative to the body, a knife part carried by the carrier for forcible projection therefrom, fluid pressure generating means carried by the body operable to move the said knife part.

tion of said part.

tool operable to part the couplings of a object in a well 17. A tool operable to tubular object in a well and adapted to be operating means is utilized in the projection of said part, and means operable `by vertical manipulation of the line for operating the fluid pressure generating means.

18. A tool useful in parting a tubular object in a well and adapted to be operated on a ilexible line, the tool comprising a body assembly to be lowered into the object, means for connecting the body assembly with the line for lowering and operation thereby, gripping means carject, a knife part carried by the body assembly for projection therefrom, means carried by the body assembly for generating fluid pressure, means operable by the pressure thus generated for projecting said part against the object, a control operable by vertical manipulation of the line for actuating the last named means, and means operable by by vertical manipulation of the line for' retracting said gripping means and GLENN D. JOHNSON. 

